Hand-held surgical instruments

ABSTRACT

A hand-held surgical instrument includes a handle housing, a shaft portion extending distally from the handle housing, and an articulation shaft. The articulation shaft may be configured to axially move within the shaft portion to articulate an end effector via a manual activation or a motor activation.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of and priority to U.S. ProvisionalApplication No. 62/948,870 filed on Dec. 17, 2019, the entire contentsof which are incorporated by reference herein.

BACKGROUND 1. Technical Field

The disclosure relates to surgical instruments. More specifically, thedisclosure relates to hand-held electromechanical surgical instrumentsthat articulate, rotate, and actuate a variety of other functions ofsurgical attachments, such as, for example, end effectors configured tostaple tissue.

2. Background of Related Art

Electromechanical surgical instruments include a reusable handleassembly and disposable loading units and/or single use loading units,such as, for example, surgical end effectors. The end effectors areselectively connected to the handle assembly prior to use and thendisconnected from the handle assembly following use in order to bedisposed of or in some instances sterilized for re-use. Some surgicalinstruments may be capable of articulating the end effector to adjustthe angle of orientation of the end effector during a surgicalprocedure. There are one or more drive mechanisms within the handleassembly for carrying out the articulation of the end effector and/orthe operational functions of the end effector.

SUMMARY

In one aspect of the disclosure, a hand-held surgical instrument isprovided and includes a handle housing, a shaft portion extendingdistally relative to the handle housing, a first motor disposed withinthe handle housing, a ball screw operably coupled to the first motor, aball nut non-rotationally supported in the shaft portion and operablycoupled to the ball screw, and a firing shaft. The firing shaft has aproximal end portion attached to the ball nut, and a distal end portionconfigured to fire staples from an end effector. The ball nut isconfigured to translate the firing shaft along a longitudinal axisdefined by the shaft portion in response to a rotation of the ballscrew.

In aspects, the hand-held surgical instrument may further include abattery configured to power the first motor. In aspects, the battery maybe configured to power all motors, LED's, and various other electronics.

In some aspects, the handle housing may have a barrel portion, and ahandle portion extending perpendicularly from the barrel portion. Thebattery may be supported in the handle portion. In aspects, the batterymay be supported in the barrel portion.

In other aspects, the handle portion may include an upper segment fixedto the barrel portion, and a lower segment pivotably coupled to theupper segment, the battery being disposed in the lower segment.

In further aspects, the handle portion may define a plane that extendsparallel with the longitudinal axis of the shaft portion. The lowersegment may be configured to pivot relative to the upper segment about apivot axis that is parallel with the plane.

In aspects, the hand-held surgical instrument may further include aprinted circuit board supported in the upper segment and configured tobe in electrical communication with the battery and the first motor. Inaspects, the printed circuit board may be in electrical communicationwith motion control circuitry.

In some aspects, the hand-held surgical instrument may further include afinger switch pivotably coupled to the upper segment. The finger switchmay have an upper button and a lower button each in communication withthe printed circuit board for activating the battery. In aspects, thefinger switch may activate the battery and control the first motor.

In further aspects, the hand-held surgical instrument may furtherinclude a knob housing coupled to the handle housing, an articulationlever, and a first articulation shaft. The shaft portion may extenddistally from the knob housing. The articulation lever may berotationally coupled to the knob housing. The first articulation shaftmay be operably coupled to the articulation lever, such that a rotationof the articulation lever translates the first articulation shaft toarticulate an end effector.

In other aspects, the hand-held surgical instrument may further includea cam plate coupling the articulation lever with a proximal end portionof the first articulation shaft. The cam plate may be configured to urgethe first articulation shaft in one of a proximal or distal directionupon rotation of the cam plate.

In aspects, the hand-held surgical instrument may further include anarticulation locking assembly that includes a first ratchet gearoperably coupled to the cam plate and a pawl engaged with the firstratchet gear. The pawl may be configured to restrict the rotation of thecam plate.

In some aspects, the first ratchet gear may be non-rotationally coupledto the articulation lever and pinned to the cam plate, such that arotation of the articulation lever rotates the cam plate.

In further aspects, the cam plate may have a pin that extends through anelongate slot defined in the first ratchet gear. The first ratchet gearmay be configured to rotate the cam plate after a delay.

In other aspects, the articulation locking assembly may include a secondratchet gear disposed between the first ratchet gear and the cam plate.The pawl may be engaged with the first and second ratchet gears.

In aspects, the first ratchet gear may have a plurality of teeth eachdefining an oblique surface, and the second ratchet gear may have aplurality of teeth each defining a linear surface.

In some aspects, adjacent teeth of the plurality of teeth of the firstratchet gear may define a triangular space therebetween, and adjacentteeth of the plurality of teeth of the second ratchet gear may define arectangular space therebetween.

In further aspects, the second ratchet gear may be fixed to the camplate, such that the cam plate and the second ratchet gear rotatesimultaneously with one another.

In other aspects, the cam plate may define a first spiral slot, and theproximal end portion of the first articulation shaft may have aprotuberance received in the first spiral slot.

In aspects, the hand-held surgical instrument may further include asecond articulation shaft having a protuberance extending from aproximal end portion thereof. The protuberance of the secondarticulation shaft may be received in a second spiral slot defined inthe cam plate. The first and second articulation shafts may beconfigured to translate in opposite directions in response to a rotationof the cam plate.

In accordance with another aspect of the disclosure, a hand-heldsurgical instrument is provided and includes a handle housing, a knobhousing coupled to the handle housing, a shaft portion extendingdistally from the knob housing, an articulation lever rotationallycoupled to the knob housing, a first articulation shaft, a cam plate,and an articulation locking assembly. The first articulation shaft isoperably coupled to the articulation lever, such that a rotation of thearticulation lever translates the first articulation shaft to articulatean end effector. The cam plate couples the articulation lever with aproximal end portion of the first articulation shaft. The cam plate isconfigured to urge the first articulation shaft in one of a proximal ordistal direction. The articulation locking assembly includes a firstratchet gear operably coupled to the cam plate, and a pawl engaged withthe first ratchet gear. The pawl may be configured to restrict therotation of the cam plate.

In some aspects, the cam plate may have a pin that extends through anelongate slot defined in the first ratchet gear. The first ratchet gearmay be configured to rotate the cam plate after a delay.

In further aspects, the articulation locking assembly may include asecond ratchet gear disposed between the first ratchet gear and the camplate. The pawl may be engaged with the first and second ratchet gears.

In other aspects, the first ratchet gear may have a plurality of teetheach defining an oblique surface, and the second ratchet gear may have aplurality of teeth each defining a linear surface.

In aspects, adjacent teeth of the plurality of teeth of the firstratchet gear may define a triangular space therebetween, and adjacentteeth of the plurality of teeth of the second ratchet gear may define arectangular space therebetween,

In some aspects, the second ratchet gear may be fixed to the cam plate,such that the cam plate and the second ratchet gear rotatesimultaneously with one another.

In further aspects, the cam plate may define a first spiral slot, andthe proximal end portion of the first articulation shaft may have aprotuberance received in the first spiral slot.

In other aspects, the hand-held surgical instrument may include a secondarticulation shaft having a protuberance extending from a proximal endportion thereof. The protuberance of the second articulation shaft maybe received in a second spiral slot defined in the cam plate. The firstand second articulation shafts may be configured to translate inopposite directions in response to a rotation of the cam plate.

In accordance with yet another aspect of the disclosure, a shaftassembly for use with a handle assembly of a hand-held surgicalinstrument is provided. The shaft assembly includes a knob housing, ashaft portion extending distally from the knob housing, an end effectorcoupled to a distal end portion of the shaft portion, an articulationlever rotationally coupled to the knob housing, a first articulationshaft, and a cam plate. The first articulation shaft is operably coupledto the articulation lever, such that a rotation of the articulationlever translates the first articulation shaft to articulate the endeffector. The cam plate couples the articulation lever with a proximalend portion of the first articulation shaft. The cam plate is configuredto urge the first articulation shaft in one of a proximal or distaldirection in response to a rotation of the cam plate.

In aspects, the shaft assembly may further include an articulationlocking assembly that includes a first ratchet gear operably coupled tothe cam plate and a pawl engaged with the first ratchet gear. The pawlmay be configured to restrict the rotation of the cam plate.

In some aspects, the first ratchet gear may be non-rotationally coupledto the articulation lever and pinned to the cam plate, such that arotation of the articulation lever rotates the cam plate.

In further aspects, the cam plate may have a pin that extends through anelongate slot defined in the first ratchet gear. The first ratchet gearmay be configured to rotate the cam plate after a delay.

In other aspects, the articulation locking assembly may include a secondratchet gear disposed between the first ratchet gear and the cam plate.The pawl may be engaged with the first and second ratchet gears.

In aspects, the first ratchet gear may have a plurality of teeth eachdefining an oblique surface, and the second ratchet gear may have aplurality of teeth each defining a linear surface.

In some aspects, adjacent teeth of the plurality of teeth of the firstratchet gear may define a triangular space therebetween, and adjacentteeth of the plurality of teeth of the second ratchet gear may define arectangular space therebetween.

In other aspects, the second ratchet gear may be fixed to the cam plate,such that the cam plate and the second ratchet gear rotatesimultaneously with one another.

In accordance with yet another aspect of the disclosure, a hand-heldsurgical instrument is provided and includes a handle housing, a shaftportion extending distally relative to the handle housing, a firstarticulation shaft supported in the shaft portion, a barrel cam, and anarticulation motor. The first articulation shaft has a distal endportion configured to operably engage an end effector. The barrel cam iscoupled to a proximal end portion of the first articulation shaft. Thearticulation motor may be operably coupled to the barrel cam andconfigured to rotate the barrel cam. A rotation of the barrel camtranslates the first articulation shaft.

In aspects, the hand-held surgical instrument may further include a knobhousing coupled to the handle housing. The knob housing may have theshaft portion extending distally therefrom. A manual rotation of theknob housing may rotate the shaft portion and the attached end effector.

In some aspects, the barrel cam may have an inner annular surfacedefining a helical cam slot. The proximal end portion of the firstarticulation shaft may have a protuberance received in the helical camslot.

In further aspects, the hand-held surgical instrument may furtherinclude a ring gear non-rotationally coupled to the barrel cam. Thearticulation motor may have a motor gear operably coupled to the ringgear, such that a rotation of the motor gear results in a rotation ofthe barrel cam.

As used herein, the terms parallel and perpendicular are understood toinclude relative configurations that are substantially parallel andsubstantially perpendicular up to about + or −10 degrees from trueparallel and true perpendicular.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the disclosure are described herein with reference to theaccompanying drawings, wherein:

FIG. 1 is a perspective view of a hand-held electromechanical surgicalinstrument including a handle assembly, a shaft portion coupled to thehandle assembly, and a surgical end effector coupled to the shaftportion, in accordance with an embodiment of the disclosure;

FIG. 2 is an enlarged side view, with a handle housing half removed, ofthe surgical instrument of FIG. 1 ;

FIG. 3 is a rear perspective view illustrating a handle portion of thesurgical instrument in an open state for removing a battery;

FIG. 4 is a side cross-sectional view of the handle portion of FIG. 3 ,as taken through 4-4 of FIG. 3 ;

FIG. 5 is a longitudinal cross-sectional view, as taken through 5-5 ofFIG. 1 , illustrating a drive motor and a ball screw assembly foroperating a stapling function of the end effector;

FIG. 6 is a perspective view, with parts separated, of a ball nut of theball screw assembly of FIG. 5 ;

FIG. 7 is a side perspective view illustrating the shaft assembly of thesurgical instrument of FIG. 1 ;

FIG. 8 is a perspective view, with parts separated, illustratingcomponents of an articulation assembly of the shaft assembly of FIG. 7 ;

FIG. 9 is an enlarged perspective view, of the indicated area of detailof FIG. 8 , illustrating first and second articulation shafts of thearticulation assembly of FIG. 8 ;

FIG. 10 is a perspective view, with parts separated, illustrating acamming mechanism of the articulation assembly of FIG. 8 ;

FIG. 11 is a perspective view, with parts separated, illustrating anarticulation locking assembly of the shaft assembly of FIG. 7 ;

FIG. 12 is a top view illustrating the articulation locking assembly ofFIG. 11 ;

FIG. 13 is a side view illustrating another embodiment of a hand-heldelectromechanical surgical instrument including a handle assembly, ashaft portion coupled to the handle assembly, and a surgical endeffector coupled to the shaft portion; and

FIG. 14 is a perspective view, with parts separated, illustratingcomponents of an articulation assembly of the surgical instrument ofFIG. 13 .

DETAILED DESCRIPTION

Embodiments of the presently disclosed surgical instruments aredescribed in detail with reference to the drawings, in which likereference numerals designate identical or corresponding elements in eachof the several views. As used herein the term “distal” refers to thatportion of the surgical instrument, or component thereof, farther fromthe user, while the term “proximal” refers to that portion of thesurgical instrument, or component thereof, closer to the user.

With reference to FIGS. 1 and 2 , a surgical instrument, in accordancewith an embodiment of the disclosure, is generally designated as 10, andis in the form of a powered hand-held electromechanical surgicalinstrument configured for selective coupling thereto of a plurality ofdifferent surgical end effectors, for example, the surgical end effector20. The end effector 20 is configured for actuation and manipulation bythe powered hand-held electromechanical surgical instrument 10.

The hand-held electromechanical surgical instrument 10 includes a handleassembly 12 and a shaft portion 14 extending distally from the handleassembly 12. The shaft portion 14 is configured for selective connectionwith a surgical attachment, such as, for example, the end effector 20.The handle assembly 12 has a fire switch 16 configured to actuate thevarious functions of the end effector 20. In addition, the handleassembly 12 has a safety switch 18 for preventing an inadvertentactuation of the fire switch 16. A knob housing 22 is rotationallycoupled to the handle assembly 12 and configured to be manually rotatedabout a longitudinal axis “X” defined by the shaft portion 14 to rotatethe end effector 20. An articulation lever 24 is rotationally coupled tothe knob housing 22 and is configured to articulate the end effector 20(e.g., move the end effector 200 along a horizontal plane between aposition coaxial with the shaft portion 14 and multiple positions out ofalignment with the shaft portion 14. The angular orientation of alongitudinal axis of the articulation lever relative to the longitudinalaxis “X” corresponds to an angular orientation of a longitudinal axis ofthe end effector 20 relative to the longitudinal axis “X.” As such, theend effector 20 may articulate in the same direction and to the sameangular extent as the articulation lever 24.

With reference to FIGS. 2-4 , the handle assembly 12 includes a handlehousing 26 consisting of a barrel portion 28 substantially aligned withthe longitudinal axis “X,” and a handle portion 30 extendingperpendicularly downward from the barrel portion 28. The handle portion30 includes an upper segment 32 fixed to and extending downwardly fromthe barrel portion 28, and a lower segment 34 pivotably coupled to theupper segment 32. The handle assembly 12 includes a printed circuitboard 36 supported in the upper segment 32 and a battery 38 disposed inthe lower segment 34. The printed circuit board 36 is configured to bein electrical communication with the battery 38 and a drive motor 40.The motor 40 may be wirelessly connected, connected via a wire, orotherwise electrically connected to the printed circuit board 36 and thebattery 38. The fire switch 16 may be a finger switch pivotably coupledto the upper segment 32 and has an upper button 16 a and a lower button16 b each in communication with the printed circuit board 36 foractivating the battery 38 to ultimately actuate an open/close and staplefiring function of the end effector 20.

As shown in FIGS. 3 and 4 , the upper segment 32 of the handle portion30 has a flange 42, such as, for example, a tab, extending downwardlytherefrom, and the lower segment 34 defines a cutout 44 configured forreceipt of the flange 42. The flange 42 has an inner surface having adeflectable latch hook 46 at an end thereof, and the lower segment 34includes a release button 48 having a tab 50 extending into the cutout44. The tab 50 of the release button 48 defines a notch 52 configured toselectively receive and lock with the latch hook 46 of the upper segment32. In some aspects, the upper and lower segments 32, 34 may detachablycouple to one another via any suitable fastening connection, such as,for example, a bayonet-type connection. The upper and lower segments 32,34 are pivotably coupled to one another about a hinge 54, such as, forexample, a pivot pin. The handle portion 30 defines a plane that extendsparallel with the central longitudinal axis “X” of the shaft portion 14,such that the lower segment 34 is pivotable relative to the uppersegment 32 about a pivot axis “Y” (FIG. 2 ) that is parallel with theplane.

With reference to FIGS. 5 and 6 , the surgical instrument 10 furtherincludes a ball screw assembly 56 operably coupled to the motor 40 forcarrying out an open/close and stapling function of the end effector 20(FIG. 1 ). The ball screw assembly 56 includes a ball nut 58, a ballscrew 60, and a firing shaft 62. The ball screw 60 is drivingly coupledto the motor 40 such that an actuation of the motor 40 results in arotation of the ball screw 60. The ball nut 58 is non-rotationallysupported in the shaft portion 14 and operably coupled to the ball screw60. In particular, the ball nut 58 may have first and second planarlateral sides 58 a, 58 b that inhibit rotation of the ball nut 58relative to the shaft portion 14, and the ball nut 58 has an innersurface defining threading 64 that houses bearings (not shown). Thebearings are captured between the threading 64 of the ball nut 58 and athreaded outer surface of the ball screw 60.

The firing shaft 62 defines a conduit 66 through a proximal end portion62 a thereof. The ball screw 60 extends through the conduit 66 and theproximal end portion 62 a is fixed to the ball nut 58. In this way, thefiring shaft 62 moves with the ball nut 58 as the ball nut 58 movesaxially within the shaft portion 14 and relative to the ball screw 60.The firing shaft 62 has a distal end portion 62 b configured to operablycouple to an axially-driven member (not shown) of the end effector 20.The ball nut 58 has a cap or cover 68 for containing the ball bearingstherein.

FIGS. 7-10 illustrate a shaft assembly 70 of the surgical instrument 10.The shaft assembly 70 includes the knob housing 22, the shaft portion14, and the end effector 20. The knob housing 22 supports anarticulation assembly 72 configured to effect the articulation of theend effector 20 relative to the shaft portion 14. The articulation lever24 of the articulation assembly 72 is accessible from outside of theknob housing 22 and is configured to be manually rotated.

The articulation assembly 72 generally includes first and secondarticulation shafts 74, 76 and a cam plate 82. The first and secondarticulation shafts 74, 76 are axially movable within the shaft portion14 and each has a proximal end portion 74 a, 76 a operably coupled tothe articulation lever 22, and a distal end portion (not explicitlyshown) operably coupled to opposite sides of the end effector 20. Assuch, a rotation of the articulation lever 22 translates the first andsecond articulation shafts 74, 76 in opposite directions to articulatethe end effector 20. The proximal end portion 74 a, 76 a of each of thearticulation shafts 74, 76 has a respective protuberance 78, 80. The camplate 82 defines first and second spiral slots 82 a, 82 b for receivingthe respective protuberances 78, 80. The spiral cam slots 82 a, 82 b areoriented so that a rotation of the cam plate 82 results in an axialmovement of the first and second articulation shafts 74, 76 in oppositedirections. A helical coil 84 may be attached to the proximal endportion of the shaft portion 14 for guiding an electrical cable (notshown) thereabout that runs from the motor 40 (FIG. 5 ). The helicalcoil 84 rotates with a rotation of the shaft portion 14 and prevents thecable from bunching and eliminates the need for an electrical slip ring.

FIGS. 11 and 12 illustrate an articulation locking assembly 88 forselectively locking the articulation lever 22 in a rotational positionto prevent backdriving of the articulation lever 22. The articulationlocking assembly 88 generally includes a ratchet assembly 90 operablycoupling the cam plate 82 and the articulation lever 22, and a pawl 92engaged with the ratchet assembly 90 and configured to restrict therotation of the cam plate 82. The pawl 92 has a proximal end portion 92a slidably supported on the spiral coil 84, and a free distal endportion 92 b having an elongated distal tip 94. The pawl 92 is slidablealong a longitudinal axis defined by the pawl 92. A detent spring 96(FIG. 10 ) is provided to resiliently bias the distal tip 94 of the pawl92 in a distal direction. In aspects, the pawl 92 may be resilient orrigid.

The ratchet assembly 90 includes a first ratchet gear 98 and a secondratchet gear 100. The first ratchet gear 98 has a plate 102 and a stem104 extending from the plate 102. The stem 104 is received in acorrespondingly shaped aperture (not explicitly shown) defined in thearticulation lever 22 to non-rotationally couple the first ratchet gear98 to the articulation lever 22. The plate 102 of the first ratchet gear98 has a plurality of teeth 106 arranged around the outer periphery ofthe first ratchet gear 98. Each of the teeth 106 defines an obliquesurface 108, such that adjacent teeth 106 define a triangular space 110therebetween configured for selective receipt of the free distal tip 94of the pawl 92.

The plate 102 of the first ratchet gear 98 is coupled to the cam plate82, such that a rotation of the articulation lever 22 rotates the camplate 82. For example, the cam plate 82 has a pair of pins 112, 114 thatextend through a respective elongate slot 116, 118 defined in the firstratchet gear 98. The elongate slots 116, 118 define a length that isapproximately 1.5 times greater than a diameter of the pins 112, 114 ofthe cam plate 82. In this way, a rotation of the first ratchet gear 98,in response to a rotation of the articulation lever 22, results in arotation of the cam plate 82 after a delay.

The second ratchet gear 100 is disposed between the plate 102 of thefirst ratchet gear 98 and the cam plate 82. The second ratchet gear 100is fixed to the cam plate 82 (e.g., via the pins 112, 114), such thatthe cam plate 82 and the second ratchet gear 100 rotate simultaneouslywith one another. The second ratchet gear 100 has a plurality of teeth120 arranged around an outer periphery thereof. The teeth 120 of thesecond ratchet gear 100 each define a linear surface 122, such thatadjacent teeth 120 of the second ratchet gear 100 define a rectangularspace 124 therebetween configured for selective receipt of the distaltip 94 of the pawl 92. The distal tip 94 of the pawl 92 may beconfigured to wedge into the space 124 to resist rotation of the secondratchet gear 100 relative to the pawl 92.

The first and second ratchet gears 98, 100 are angularly orientedrelative to one another so that the triangular spaces 110 of the firstratchet gear 98 overlap with the respective rectangular spaces 124 ofthe second ratchet gear 100. In aspects, the spaces 110 of the firstratchet gear 98 may assume the same shape as the spaces 124 of thesecond ratchet gear 100 and/or the spaces 110, 124 may assume anysuitable shape, such as, for example, arcuate.

In operation, to articulate the end effector 20, the articulation lever22 may be manually rotated in the direction intended for the endeffector 20 to articulate. Rotation of the articulation lever 22 rotatesthe first ratchet gear 98, whereby one of the oblique surfaces 108 ofthe teeth 106 of the first ratchet gear 98 cams the free distal tip 94of the pawl 92 proximally and out of the space 110 between the teeth 106of the first ratchet gear 98 and the space 124 between the teeth 120 ofthe second ratchet gear 100. A tooth 106 of the first ratchet gear 98 isrotated into overlapping alignment with a space 124 defined betweenadjacent teeth 120 of the second ratchet gear 100, whereby the firstratchet gear 98 engages the pins 112, 114 of the cam plate 82 to drive arotation of the cam plate 82. As described, rotation of the cam plate 82translates the first and second articulation shafts 74, 76 in oppositedirections. The opposing translation of the first and secondarticulation shafts 74, 76 drives the articulation of the end effector20.

Due to the second ratchet gear 100 being fixed to the cam plate 82, thesecond ratchet gear 100 rotates with the cam plate 82 to maintain theteeth 106 of the first ratchet gear 98 in overlapping alignment withrespective spaces 124 of the second ratchet gear 100. In this way, thedistal tip 94 of the pawl 92 is maintained in a proximal position andout of the spaces 110, 124 of the ratchet gears 98, 100 while thearticulation lever 22 is being rotated. However, upon removing theapplication of a rotational force on the articulation lever 22, theresilient bias of the pawl 92 (due to detent spring 96) will cam thefirst ratchet gear 98 to reposition the teeth 106 of the first ratchetgear 98 into overlapping alignment with the teeth 120 of the secondratchet gear 100. This is caused by the first ratchet gear 98 being freeto rotate relative to the second ratchet gear 100 a selected distance.Despite any backdriving force exerted on the second ratchet gear 100 viathe cam plate 82, rotation of the second ratchet gear 100 is resisteddue to the engagement of the distal tip 94 of the pawl 92 in the space124 of the second ratchet gear 100. More specifically, the adjacentteeth 120 of the second ratchet gear 100 capture the distal tip 94 ofthe pawl 92 therebetween, thereby resisting rotation of the secondratchet gear 100 and, in turn, the cam plate 82.

FIGS. 13 and 14 illustrate another embodiment of a hand-held surgicalinstrument 210, similar to the surgical instrument 10 described above.The surgical instrument 210 is different by having a poweredarticulation mechanism 220 rather than being manually actuated. Due tothe similarities between the two surgical instruments, only thoseelements of the surgical instrument 210 deemed necessary to elucidatethe differences from the surgical instrument 10 will be described indetail.

The surgical instrument 210 generally includes a handle housing 212, aknob housing 222 coupled to the handle housing 212, a shaft portion 214extending distally from the knob housing 222, and an end effector, suchas, for example, the end effector 20, operably coupled to a distal endportion of the shaft portion 214. An articulation switch 216 ispivotably coupled to the handle housing 212 for actuating anarticulation of the end effector 20. The knob housing 222 may bemanually rotated to thereby rotate the shaft portion 214 and theattached end effector 20 about a longitudinal axis defined by the shaftportion 214. The shaft portion 214 has a first articulation shaft 274and a second articulation shaft (not explicitly shown) each supportedtherein.

The articulation mechanism 220 is received at least partially in theknob housing 222 and includes a barrel cam 224, a barrel cam gear 226,and an articulation motor 228. The barrel cam 224 consists of first andsecond semicircular half sections 224 a, 224 b together forming atubular barrel cam 224. The barrel cam 224 is received within and fixedto the barrel cam gear 226. In some aspects, the barrel cam 224 may bemonolithically formed with the barrel cam gear 226. Each of the firstand second semicircular half sections 224 a, 224 b of the barrel cam 224defines opposing helical cam slots 230 in an inner annular surface 232thereof. The helical cam slots 230 receive a respective protuberanceextending from the proximal end portion of the first and secondarticulation shafts 274. As such, a rotation of the barrel cam 224results in axial translation of the first and second articulation shafts274 in opposite directions.

The barrel cam gear 226 has a tubular body 226 a and a ring gear 226 bfixed about the tubular body 226 a. The articulation motor 228 has adrive shaft 236 and a drive gear 238 non-rotationally coupled to thedrive shaft 236. The drive gear 238 of the articulation motor 228 isoperably coupled to the ring gear 226 b to rotate the barrel cam 224 totranslate the first and second articulation shafts 274.

In operation, an articulation switch 217 may be actuated to activate thearticulation motor 228 to rotate the drive gear 238. Rotation of thedrive gear 238 drives a rotation of the barrel cam 224 via the ring gear226 b. Due to the protuberances or pins of the articulation shafts 274being received in the opposing helical cam slots 230 of the barrel cam224, rotation of the barrel cam 224 drives an axial translation of thefirst and second articulation shafts 274 in opposing directions toarticulate the end effector 20 relative to the shaft portion 214.

Any of the components described herein may be fabricated from eithermetals, plastics, resins, composites or the like taking intoconsideration strength, durability, wearability, weight, resistance tocorrosion, ease of manufacturing, cost of manufacturing, and the like.

It will be understood that various modifications may be made to theembodiments of the presently disclosed surgical instruments includingswitch assemblies. Therefore, the above description should not beconstrued as limiting, but merely as exemplifications of embodiments.Those skilled in the art will envision other modifications within thescope and spirit of the disclosure.

1. (canceled)
 2. A hand-held surgical instrument, comprising: a handle housing; a knob housing coupled to the handle housing; a shaft portion extending distally from the knob housing; an articulation lever rotationally coupled to the knob housing; a first articulation shaft operably coupled to the articulation lever, such that a rotation of the articulation lever translates the first articulation shaft to articulate an end effector; a cam plate coupling the articulation lever with a proximal end portion of the first articulation shaft, the cam plate being configured to urge the first articulation shaft in one of a proximal or distal direction; and an articulation locking assembly including: a first ratchet gear operably coupled to the cam plate; and a pawl engaged with the first ratchet gear, wherein the pawl is configured to restrict the rotation of the cam plate.
 3. The hand-held surgical instrument according to claim 2, wherein the first ratchet gear is non-rotationally coupled to the articulation lever and pinned to the cam plate, such that a rotation of the articulation lever rotates the cam plate.
 4. The hand-held surgical instrument according to claim 3, wherein the cam plate has a pin that extends through an elongate slot defined in the first ratchet gear, the first ratchet gear configured to rotate the cam plate after a delay.
 5. The hand-held surgical instrument according to claim 4, wherein the articulation locking assembly includes a second ratchet gear disposed between the first ratchet gear and the cam plate, the pawl being engaged with the first and second ratchet gears.
 6. The hand-held surgical instrument according to claim 5, wherein the first ratchet gear has a plurality of teeth each defining an oblique surface, and the second ratchet gear has a plurality of teeth each defining a linear surface.
 7. The hand-held surgical instrument according to claim 6, wherein adjacent teeth of the plurality of teeth of the first ratchet gear define a triangular space therebetween, and adjacent teeth of the plurality of teeth of the second ratchet gear define a rectangular space therebetween.
 8. The hand-held surgical instrument according to claim 5, wherein the second ratchet gear is fixed to the cam plate, such that the cam plate and the second ratchet gear rotate simultaneously with one another.
 9. The hand-held surgical instrument according to claim 2, wherein the cam plate defines a first spiral slot, and the proximal end portion of the first articulation shaft has a protuberance received in the first spiral slot.
 10. The hand-held surgical instrument according to claim 9, further comprising a second articulation shaft having a protuberance extending from a proximal end portion thereof, the protuberance of the second articulation shaft received in a second spiral slot defined in the cam plate, the first and second articulation shafts configured to translate in opposite directions in response to a rotation of the cam plate.
 11. The hand-held surgical instrument according to claim 2, wherein: the cam plate includes a pair of pins extending therefrom, wherein the pair of pins of the cam plate are located on opposed sides of the longitudinal axis defined by the shaft portion and extend parallel to the longitudinal axis; and the first ratchet gear defines a pair of elongate slots formed therein, wherein each pin of the pair of pins of the cam plate is slidably received in a respective slot of the pair of elongate slots formed in the first ratchet plate.
 12. A shaft assembly for use with a handle assembly of a hand-held surgical instrument, the shaft assembly comprising: a knob housing; a shaft portion extending distally from the knob housing; an end effector coupled to a distal end portion of the shaft portion; an articulation lever rotationally coupled to the knob housing; a first articulation shaft operably coupled to the articulation lever, such that a rotation of the articulation lever translates the first articulation shaft to articulate the end effector; and a cam plate coupling the articulation lever with a proximal end portion of the first articulation shaft, wherein the cam plate is configured to urge the first articulation shaft in one of a proximal or distal direction in response to a rotation of the cam plate.
 13. The shaft assembly according to claim 12, further comprising an articulation locking assembly including: a first ratchet gear operably coupled to the cam plate; and a pawl engaged with the first ratchet gear, wherein the pawl is configured to restrict the rotation of the cam plate.
 14. The shaft assembly according to claim 13, wherein the first ratchet gear is non-rotationally coupled to the articulation lever and pinned to the cam plate, such that a rotation of the articulation lever rotates the cam plate.
 15. The shaft assembly according to claim 14, wherein the cam plate has a pin that extends through an elongate slot defined in the first ratchet gear, the first ratchet gear being configured to rotate the cam plate after a delay.
 16. The shaft assembly according to claim 15, wherein the articulation locking assembly includes a second ratchet gear disposed between the first ratchet gear and the cam plate, the pawl being engaged with the first and second ratchet gears.
 17. The shaft assembly according to claim 16, wherein the first ratchet gear has a plurality of teeth each defining an oblique surface, and the second ratchet gear has a plurality of teeth each defining a linear surface.
 18. The shaft assembly according to claim 17, wherein adjacent teeth of the plurality of teeth of the first ratchet gear define a triangular space therebetween, and adjacent teeth of the plurality of teeth of the second ratchet gear define a rectangular space therebetween.
 19. The shaft assembly according to claim 16, wherein the second ratchet gear is fixed to the cam plate, such that the cam plate and the second ratchet gear rotate simultaneously with one another.
 20. The shaft assembly according to claim 12, wherein: the cam plate includes a pair of pins extending therefrom, wherein the pair of pins of the cam plate are located on opposed sides of the longitudinal axis defined by the shaft portion and extend parallel to the longitudinal axis; and the first ratchet gear defines a pair of elongate slots formed therein, wherein each pin of the pair of pins of the cam plate is slidably received in a respective slot of the pair of elongate slots formed in the first ratchet plate. 